In flat-panel display device, thin film transistor liquid crystal displays (TFT-LCD) have become the dominant product for its small size, low power dissipation, relatively low cost and no irradiation.
At present, the main structure of TFT-LCD comprises an array substrate and a color filter (CF) substrate, wherein the CF substrate mainly comprises a glass substrate, a black matrix (BM), a color photoresist and an outside cover. The main effect of the color photoresist is to provide the three-primary colors of Red, Green and Blue by means of light-filtering and then mix the three-primary colors in different ratio in terms of strength so as to obtain a variety of colors, thereby presenting full-color by the TFT-LCD.
A color photoresist is a cured film obtained by coating a photoresist composition, photo-curing and developing. Usually, the main components of a photoresist composition include an alkali-soluble resin, a polymerizable monomer having high degree of functionality, an initiator, a pigment dispersion, an organic solvent, etc. When the polymerizable monomer having high degree of functionality has aromatic ring or ether chain, the cured film formed by the photoresist comprising such monomer will yellowing badly, i.e. the color-change phenomenon is serious, and the transmittance thereof is low.
Thus, it is desired to provide an improved photoresist composition which can reduce the yellowing phenomenon and increase the transmittance.